So what's so radical about social bookmarking? How is it more exciting than Google? Well, on a purely practical level, it's a godsend to anybody who uses more than a single computer: now, your bookmarks can be accessed anywhere. But more interesting is the kind of information it enables us to retrieve from the internet. The Google robot might seem ingenious, but it stumbles through the supermarkets and slums of the web without distinguishing them from the libraries and museums. Compared with real internet users, choosing and saving the most interesting websites, it's very dumb. social bookmarking separates the information from the trash, and turns searching into an art form.
—Linton Chiswick, "Track clickerati's new buzz," Financial Times (London, England), September 24, 2005

This paper reviews some current initiatives, as of early 2005, in providing public link management applications on the Web — utilities that are often referred to under the general moniker of 'social bookmarking tools'. There are a couple of things going on here: 1) server-side software aimed specifically at managing links with, crucially, a strong, social networking flavour, and 2) an unabashedly open and unstructured approach to tagging, or user classification, of those links.
—Tony Hammond, Timo Hannay, Ben Lund, and Joanna Scott, "Social Bookmarking Tools," D-Lib Magazine, April 1, 2005

In last week’s column, I mentioned del.icio.us, Joshua Schachter’s "social bookmarking" service.
—Jon Udell, "The human information filter," InfoWorld, August 27, 2004